Active hyperemia, changes in local pH and mechanical forces promote bone resorption. Gorham and Stout hypothesized that trauma may trigger the process by stimulating the production of vascular granulation tissue and that “osteoclastosis” is not necessary.[1] Whereas, Devlin et al., have suggested that bone resorption in patients with Gorham disease is due to enhanced osteoclast activity and interleukin 6 plays a role in the increased resorption of bone.[6] Evidence that osteolysis is due to an increased number of stimulated osteoclasts was presented by Moller et al.,[8] Cellular and humoral mechanisms of osteoclast formation and bone resorption was reported by Hirayama et al., which suggested that the increase in osteoclast is not due to an increase in the number of circulating osteoclast precursors, but rather is due to an increase in the sensitivity of these precursors to humoral factors, which promote osteoclast formation and bone resorption.[9] It has also been suggested that thyroid C cells and calcitonin may play an important role in the pathogenesis of Gorham's disease.[10]